An internal bust-up over gay marriage is threatening to embarrass the SDLP after an MLA was accused of going beyond his authority on the controversial issue.

There have been calls for the SDLP to clarify its position after a South Belfast MLA said the party was fully behind a change in the law to legalise same-sex marriage.

But Conall McDevitt was accused of overstepping the mark during a debate this week.

During the Belfast Pride Talks Back event, Mr McDevitt said his party was “100%” behind moves to permit gay marriage — but went further and claimed two veteran councillors would be disciplined over their opposition to it.

He was referring to former Belfast Lord Mayors Pat McCarthy and Pat Convery, who refused to take part in a vote on the issue at the City Hall last month.

Mr McDevitt’s comments sparked outrage in the party.

As vice chair of the SDLP executive, Mr Convery is more senior in the party than Mr McDevitt.

One veteran party source said gay marriage was causing divison within the SDLP.

“The issue of supporting gay marriage is not party policy,” he said.

“It never went before the party conference and has never been discussed by the party executive.

“Conall McDevitt was totally out of order saying that we are 100% behind this and he knows it.”

The SDLP group leader in City Hall, Tim Attwood, and councillors Nichola Mallon, Bernie Kelly and Colin Keenan voted in favour of the Sinn Fein proposal.

Mr Attwood said: “There is no disciplinary issue on this matter. The facts are that the SDLP voted for the motion and ensured that the motion was passed.”

An SDLP spokesman said the party supports “equal marriage”.

“Individual members may act in accordance with their personal conscience, but the party’s position is clear,” he said.

Mr McDevitt was unavailable for comment last night.

It is understood all of those involved have been told not to talk to the Press.

Background

Belfast City Council became the first local authority in Ireland to pass a motion backing same-sex marriage on July 4. It was passed 21-0 — although unionists walked out before the vote. The Civil Partnership Act provides same-sex couples with similar legal rights to married couples. But the law does not allow such unions to be referred to as marriages.